1. Field of Invention
The present invention relates to a dew condensation preventing device of a head lamp for a vehicle, and more particularly, to a dew condensation preventing device of a head lamp which can prevent dew from condensing on an inner surface of a head lamp lens installed at both left and right head lamp housings of a vehicle.
2. Description of Related Art
In general, head lamps for vehicles are mounted at front left and right sides of vehicle bodies to emit the light from the lamps in a forward direction of the vehicle so that a driver can safely drive the vehicle at night. In particular, the light is emitted forward to obtain a field of vision in the forward direction of the vehicle when driving at night or in rain.
FIG. 1 is a view illustrating a head lamp for a vehicle in the related art.
In the head lamp for the vehicle in the related art, as shown FIG. 1, it is preferable that a head lamp 2 installed to the vehicle is maintained in a clean state in which dew does not condense on the lens cover of the head lamp. However, the dew condenses on the inner surface of the head lamp lens due to a temperature difference between inner and outer portions of the head lamp 2.
In order to remove the dew condensed on the inner surface of the head lamp lens, various methods have employed in the art. For example, a head lamp housing is provided with a vent, or is provided with a moisture absorbent, thereby removing moisture. Alternatively, a lens of the head lamp is applied by a hydrophilic coating so that even though dew condenses on the lens, it cannot be seen.
The head lamp for the vehicle in the related art has some problems in that, since the method of evaporating the moisture through heat transfer caused by convection utilizes the heat generated from a bulb, which is installed to the head lamp, as an energy source capable of moving inner air, a separate device is necessary to forcefully move the air; in the case of introducing air, alien substances such as dust flow in to decrease the emitting ability of the head lamp; in the case of utilizing the moisture absorbent, the moisture absorbent is saturated, the function of absorbing the moisture is lost; and in the case of applying the hydrophilic coating to the lens of the head lamp, the cost is increased, and the hydrophilic capability is lost when a lot of moisture condenses.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.